Embodiments of the present invention generally relate to implantable medical devices, and more particularly to communicating between implantable medical devices and external devices.
An implantable medical device (“IMD”) is a medical device that is configured to be implanted within a patient anatomy and commonly employ one or more leads with electrodes that either receive or deliver voltage, current or other electromagnetic pulses (generally “energy”) from or to an organ or tissue for diagnostic or therapeutic purposes. In general, IMDs include a battery, electronic circuitry, such as a pulse generator and/or a processor module, that are hermetically sealed within a metal housing (generally referred to as the “can”), and a microprocessor that is configured to handle RF communication with an external device, as well as control patient therapy.
IMDs are programmed and monitored by an external programmer or external home-based patient care system. RF circuitry and an antenna are embedded within the housing of the external programmer and base station to allow data communication with the IMD. For example, a patient may have an IMD that communicates with a base station within the patient's home or a programmer that is used by physicians to change settings within the IMD and/or retrieve data from the IMD. The base station or external programmer device receives data from the IMD about the patient's physiological state. For example, the IMD may transmit stored data or sensed physiological parameters to the base station. Based on the received data, the base station or external programmer device may adjust operating parameters for the IMD.
In general, the IMDs and external programmers or base stations communicate bi-directionally using the Medical Implant Communication Service (“MICS”) specification. The MICS specification is defined under 47 C.F.R. 95.601-95.673 Subpart E (incorporated herein by reference) and ETSI EN 301 839-1 (incorporated herein by reference). The MICS protocol uses a frequency band between 402-405 MHz and a transmit power of approximately 25 microwatts.
Current external programmer and base station hardware is costly and cannot be upgraded without purchasing new equipment. Low cost off the shelf commercial goods, such as smart phones or tablet computers, currently cannot be used as a substitute. Off the shelf commercial goods are not equipped with MICS transceivers and are thus not capable of communicating bi-directionally with the IMD. Consequently, a need exits for a system that can enable off the shelf commercial goods to communicate with the IMD.